/* * Copyright (c) 2011-2018 Cisco and/or its affiliates. * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include <cdp/cdp.h> #include <vnet/ethernet/packet.h> /** \file 2 x CDP graph nodes: an "interior" node to process incoming announcements, and a "process" node to periodically send announcements. The interior node is neither pipelined nor dual-looped, because it would be very unusual to see more than one CDP packet in a given input frame. So, it's a very simple / straighforward example. */ /* * packet counter strings * Dump these counters via the "show error" CLI command */ static char *cdp_error_strings[] = { #define _(sym,string) string, foreach_cdp_error #undef _ }; /* * We actually send all cdp pkts to the "error" node after scanning * them, so the graph node has only one next-index. The "error-drop" * node automatically bumps our per-node packet counters for us. */ typedef enum { CDP_INPUT_NEXT_NORMAL, CDP_INPUT_N_NEXT, } cdp_next_t; /* * Process a frame of cdp packets * Expect 1 packet / frame */ static uword cdp_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { u32 n_left_from, *from; cdp_input_trace_t *t0; from = vlib_frame_vector_args (frame); /* array of buffer indices */ n_left_from = frame->n_vectors; /* number of buffer indices */ while (n_left_from > 0) { u32 bi0; vlib_buffer_t *b0; u32 next0, error0; bi0 = from[0]; b0 = vlib_get_buffer (vm, bi0); next0 = CDP_INPUT_NEXT_NORMAL; /* scan this cdp pkt. error0 is the counter index to bump */ error0 = cdp_input (vm, b0, bi0); b0->error = node->errors[error0]; /* If this pkt is traced, snapshoot the data */ if (b0->flags & VLIB_BUFFER_IS_TRACED) { int len; t0 = vlib_add_trace (vm, node, b0, sizeof (*t0)); len = (b0->current_length < sizeof (t0->data)) ? b0->current_length : sizeof (t0->data); t0->len = len; clib_memcpy (t0->data, vlib_buffer_get_current (b0), len); } /* push this pkt to the next graph node, always error-drop */ vlib_set_next_frame_buffer (vm, node, next0, bi0); from += 1; n_left_from -= 1; } return frame->n_vectors; } /* * cdp input graph node declaration */ /* *INDENT-OFF* */ VLIB_REGISTER_NODE (cdp_input_node, static) = { .function = cdp_node_fn, .name = "cdp-input", .vector_size = sizeof (u32), .type = VLIB_NODE_TYPE_INTERNAL, .n_errors = CDP_N_ERROR, .error_strings = cdp_error_strings, .format_trace = cdp_input_format_trace, .n_next_nodes = CDP_INPUT_N_NEXT, .next_nodes = { [CDP_INPUT_NEXT_NORMAL] = "error-drop", }, }; /* *INDENT-ON* */ /* * cdp periodic function */ static uword cdp_process (vlib_main_t * vm, vlib_node_runtime_t * rt, vlib_frame_t * f) { cdp_main_t *cm = &cdp_main; f64 poll_time_remaining; uword event_type, *event_data = 0; /* So we can send events to the cdp process */ cm->cdp_process_node_index = cdp_process_node.index; /* Dynamically register the cdp input node with the snap classifier */ snap_register_input_protocol (vm, "cdp-input", 0xC /* ieee_oui, Cisco */ , 0x2000 /* protocol CDP */ , cdp_input_node.index); snap_register_input_protocol (vm, "cdp-input", 0xC /* ieee_oui, Cisco */ , 0x2004 /* protocol CDP */ , cdp_input_node.index); #if 0 /* retain for reference */ /* with the hdlc classifier */ hdlc_register_input_protocol (vm, HDLC_PROTOCOL_cdp, cdp_input_node.index); #endif /* with ethernet input (for SRP) */ ethernet_register_input_type (vm, ETHERNET_TYPE_CDP /* CDP */ , cdp_input_node.index); /* Start w/ cdp effectively disabled */ poll_time_remaining = 86400.0; while (1) { /* sleep until next poll time, or msg serialize event occurs */ poll_time_remaining = vlib_process_wait_for_event_or_clock (vm, poll_time_remaining); event_type = vlib_process_get_events (vm, &event_data); switch (event_type) { case ~0: /* no events => timeout */ break; case CDP_EVENT_ENABLE: poll_time_remaining = 10.0; break; case CDP_EVENT_DISABLE: poll_time_remaining = 86400.0; break; default: clib_warning ("BUG: event type 0x%wx", event_type); break; } vec_reset_length (event_data); /* peer timeout scan, send announcements */ if (vlib_process_suspend_time_is_zero (poll_time_remaining)) { cdp_periodic (vm); poll_time_remaining = 10.0; } } return 0; } /* * cdp periodic node declaration */ /* *INDENT-OFF* */ VLIB_REGISTER_NODE (cdp_process_node) = { .function = cdp_process, .type = VLIB_NODE_TYPE_PROCESS, .name = "cdp-process", }; /* *INDENT-ON* */ void vnet_cdp_node_reference (void) { } /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */